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(No Model.) 2 Sheets-Sheet 1.

V J. LisTEW T. PROGES S OF AND APPARATUS FOR MANUFACTURING GAS. N0. 295,832. 7 Patented Mar 25, 1884.

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J. L. STEWART. BROGE SS OF AND APPARATUS FOR MANUFACTURING GAS;

.832. Patented Mar. 25 1884,

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lUNrren TATES PATENT Fries.

J OHN L. STEWVART, OF PHILADELPHIA, PENNSYLVANIA.

PROCESS OF AND APPAsATus FOR MANUFACTURING GAS.

SPECIFICATION forming part of Letters Patent No. 295,832, dated March 25, 1884-.

Application. filed March 23, 1883. (No modelm' To aZZ whom it may concern.-

Be it known that I, JOHN L. STEWART, of the city of Philadelphia, county of Philadelphia, and Stateof Pennsylvania, have invented an Improvement in Processes of and Apparatus for Manufacturing Gas, of which the following is a specification.

My invention has reference to processes of and apparatus for manufacturing a heating-gas from coal and steam, or an illuminating-gas from coal, steam, and oil, and commonly known as water-gas; and it consists in certain improvements therein, as fully set forth in the following specification and shown in the accompanying drawings, which form part thereof.

I The process of coking coal before it passes into the producer is not new, as it is shown in English patent to Siemens, No. 972, of 1863; but the process as set forth in this patent differs from mine, in that air'is admitted at all times and steam only used as an adjunct, while oil is not used at all. There is no intermittent process in the same sense as set forth hereinafter as he does not use closed generators.

The objectof my invention is to produce a heating or illuminating gas at a low cost, utilizing the enormous quantities of bituminous coal-dust now going to waste, in place of all 'or part of the coal now generally used in water-gas processes.

In the drawings, Figural is a sectional elevation of myimproved gas apparatus, taken on line z 2. Fig. 2 is a sectionalplan of same on line m' a". Fig. 3 is a sectional elevation of same on lineg y. Fig. 4 is a perspective view of the generator-lining, which is adapted to superheat the air and steam to be passed into said generator; and Fig. 5 is a plan View, part in section, ot a modified arrangement of superheaters, washer, and boiler.

A- is the generator, which may be of any desired construction. The steam andair may be passed into the same aboveor below the grate-bars P, the latter being the usual practice. I however prefer to provide the lower part of the generator-lining, and just above the gratebars, with a hollow air or steam back, A, of cast or wroughtiron, the 'same being shown in Fig. 4 as removed from the generator.

This cylinder A is provided with a rim on apertures A near the bottom. This back is built in the generator, asshown, the walls be ing made flush with the ribs and an annular passage being made all around at the top and bottom. This air or steam back may be made i in any othersuitable manner, if so desired. P is the usual'cleaning-door, for removing ashes and clinkers, and I? the charging-door when first starting the fire in the generator.

B is the superheater, which is supported upon a cylindrical air-receiver, F, and consists of a-lower or combustion chamber, 0, in conneotion with' the generator by a large flue, D, an arch, 0, open brick-work B, supported upon said arch, and a central hydrocarbonevaporating retort, H, built therein, the same being preferably full of open brick-work, the said retort receiving its oil from a pipe, h, in the usual manner, and, after the same has been vaporized, allowing it .to escape into the brick-work B by aperture h, where it commingles with the water-gas from the genera tor to form a hydrocarbon or illuminating gas. The products of combustion from the superheater pass out by pipe I at the top into the top of the steam-boiler I, and from the bottom of the said boiler into the flue J, which communicates with the chimney L, and also has its lower end dipping into the water inthe washer K.

J is the gaspipe connecting with the holder. The smoke pipe or chimney L is provided with a gas-tight valve, L, and the products of combustion are collected by a hood, L and passed by chimney M into the atmosphere.

The pipe 1, between the superh'e-ater and boiler, is provided with a chimney, I furnished with a door or valve, 1 and any escaping gases therefrom are collected by hood I and conveyedto the atmosphere.

E is a coking-retort, and is made tubular and preferably slightly flaring or conical, the said retort being supported upon blocks 0 and passing through chamber 0 of superheater B, flue D, and projecting into the generatorA, as

shown. If desired, there may be two or more of these retorts. The smaller end of the retort is made cylindrical, as at E, and in which a feeding-plunger, R, works, the said plunger being actuated by a water or steam engine, R, or any suitable mechanical means, and is preferably actuated by water-pressure and made to move very slowly when propelling the coal through the retort, (or at such speed as is necessary to keep the generator filled up to the proper height with coke,) and so arranged that the plunger will move back quickly, the object being to keep the coal in the retort in motion. The same can be accomplish ed by a screw or any othersuitable mechanical device. Opening into this cylinder E is a hopper, Q, provided with a charging-mouth, Q, and a stirrer, S, actuated by arod, S, to reciprocate over the entrance to the said cylinder to cause the coal-dust or slack to be fed down from said hopper into the cylinder, wherethe plunger can push it forward slowly. The retort E is open upon its generator end, and may be made of wrought or cast iron or fire-clay.

G is an air-pump, adapted to force air into the chamber'F by pipe 9 under considerable pressure. From this chamber the air, heated to a low degree, passes by pipe F into the combustion-chamber O, and its supply is controlled by a valve, f, and air is led under pressure by pipes F, provided with valves f, to one or more places around the generator A and admitted to the air-back A, where itis highly heated, and by its pressure forces its way through the holes A" into the generator. Air, if desired, can be conducted by pipes from the bottom of air-jacket A or otherwise, and admitted into the top of the generator over the fire or into fiue D at one or more points along the same.

0 are steam-pipes, and are provided with valves 0, and are used to convey steam to the back A, where it is superheated and passed to the incandescent carbon in small jets.

N is an auxiliary fire-box, and N a flue leading therefrom to the bottom of the boiler I.

The operation is as follows: A fire is built in fire-box N, valve L closed, and valve I opened,. and the products of combustion heat the water in the boiler I and generates steam. At the same time a fire is built in generator A, and blast from engine G forced into chamber F, from which it is admitted into the generator and superheater. WVhen the superheater and retort E are hot, coal dust is gradually forced through the said retort, and the heat distills off its gaseous products in the form of hydrocarbons, thereby bringing the contents thereof to the form of heated coke, which slowly drops into the generator and keeps up the supply of carbon there. Different grades of coal can be mixed in the hopper, so as to form a good solid coke while passing through the retort. When everything is heated up, the fire from fire-box N is withdrawn and the same scaled up tight, the air is shut off, and valve 1 closed, and steam is admitted to the generator A, and after being highly superheated passes into and through the red-hot carbon contained therein, by which it is decomposed, and the productscarbonic oxide and hydrogen-c0mmingling with the gas from the retort, pass into the superheater through flue D, where they meet the volatilized hydrocarbon oil from retort H, and the combined gas mixes and forms a fixed illuminating-gas while passing through the superheater, which gas passes down through the boiler I, washer K, and to holder by pipe J. When the carbon in generator A is reduced in temperature, the steam is shut off and valve L and air valves opened. The air is now blown in, and combustion again takes place, and the products from superheater B pass down through boiler I and off by chimneyL; or, if too much steam is being generated, valve I may be opened to allow the pro ducts of combustion from the superheater to pass off without passing through the boiler. The coking operation "is going on all the time, both while making gas and heating up the carbon in the generator.

To make heating-gas the process is the same, except that the admission of oil is omitted.

If the apparatus is made double-that is to say, two generators and two superheaters then it is desirable to divide the boiler by a diaphragm, I, and provide two outlet-pipes, J, and chimneys L; or, if desired. one chimney may be used, and the pipes J connected therewith by pipes having valves k. In this construction each superheater connects with one-half of the boiler by a pipe, I. If desired, two washers and two steam-boilers maybe used, or two washers and one steam-boiler may suffice.

I do not limit myself to the particular construction shown, as it may be modified in various ways without departing from 'my invention-as, for instance, the coking-retort may be heated by a separate fire.

The air-accumulator tank and air-pump, in

connection with the generator, are among the most important features in the bituminous-coal process for makihg gas as carried out in furnaces of the character illustrated in this application. Most of the accidents and explosions in the manufacture of water-gas in furnace-generators are caused by the defective air-blast and air-pipe. In the various processes as now carried on the air is conducted direct from the blower to the generator, and when the coal in the generator is heated up to the desired heat the air-blower is stopped and steam is forced through theincandescent carbon in the generator and decomposed into carbonicoxide and hydrogen gases, during which time, through detective valves between the air-blower and generator, the gas finds its way back to the blower in sufficient quantity to form with the air anexplosive compound, so that whem the blower is again started the gas ignitesand blows up the pipe, the valve, and theblower. This, by reason of frequent occurrence, is a source of serious trouble and expense. With 5 my accumulative air-tank and its connections I prevent the possibility of such an accident by running the air-pump continually, pumping air into the air-tank, and thenconducting the air from the tank to the generator in such quantityas may be required, and as there is always an air-pressure in the tank over and above that of the gas in the generator it is impossible for the gas to make its way back into the tank or the pump. Another and the most important feature of the accumulative air-blast is that I can applyit under any desired press ure, from one to forty pounds to the square inch. By this means I raise and fracture the mass of coke and fuel in the generator when- 20 by clogging the generating-chamber; This is accomplished whenever I wish, by suddenly turning on for a few seconds the full or sufficient blast under high pressure. The more the mass of incandescent fuel in the generator is fractured the greater the surface for theair to act on, and as the steam is forced into the same fine (after the air is shut off) it will follow the same crevices and fractures as the air did and come in contact with the same heated surfaces that were heated by means of the air-blast. Another advantage that the air-accumulating tank has over the blower alone is that the air can be let on very slowly at first, and then increase 35 to a blast under sufficient pressure to raise and fracture the mass of incandescent fuel in the generator, and then slow oft till the proper temperature is obtained. By this method of operatin g, better results can be secured in furnaces, in which bituminous coal is used for making gas in connection with the decomposition of steam.

It is not necessary to my process that coal- 1 dust alone be used, as small coal, either separately or in conjuction with coal-dust, may be used in the coking-retort, and, if desired, the coal-dust may be mixed with asphaltum, 820., to make the coke pack and form lumps.

I do not claim in this case the broad idea of fracturing and disintegrating the caked masses of coal or cokeby admitting to the fuel periodically sudden puffs or blasts of highly-compressed gaseous or aeriform fluid, as such matter is claimed in a separate pending application, filed by me October 9, 1883.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The herein-described process of generating gas, which consists in raising a body of carbonaceous fuel in a generator to incandes-.

cence by an air-blast, and at the same time, by means of the resulting hot gaseous products, heating up a charge of bituminous coal in a separate chamber or retort, then shutting off the air-blast, decomposing steam by passage ever it becomes caked or run together, there" through the incandescent fuel, and distilling the rich gas from the coal, and reducing it to coke by passing the hot gases resulting from the decomposed steamaround the outside of the coal-distilling retorts, discharging the hot coke from the retorts into the steam-decomposing chamber, and continuing the manufacture of gas by a repetition of the said steps in successive order, whereby bituminous coal 7 5 is economically distilled and rich gas therefrom is mixed with the water-gas, and hot coke is supplied to the decomposing-chamber.

2. The hereindescribed process of generat-' fuel to incandescence by an air-blast, and by means of the resulting hot gaseous products heating up a charge of bituminous coal, and a fixing-chamber containing refractory material, then, after shutting off the air-blast, decomposing steam in the bed of incandescent fuel,

, and by means of the resulting hothydrogen and carbonic-oxide gases distilling the rich gases from the coal by passing such gases in contact with the coal-retorts, and simultane 90. ouslyvaporizing hydrocarbon oil, then combining and fixing the water-gas, the coal-gas, and the oil=vapor in the heated fixing-chamber, discharging thecoke resulting from the distilled coal into the steam decomposing 5 chamber, and continuing the manufacture of gas by repeating the above steps in the manner described.

3. The closed generating-chamber and the connected combustion-chamber O, freely communicating therewith, in combination with the supply-pipes for air and steam, connecting as described, the horizontal coal-distilling retort extending through the combustion-chamber and opening into the generating-chamber, and the superheater placed above the combustion chamber, for the purpose described.

4. The closed generating-chamber, the combustion-chamber opening freely into it, and the superheating or fixing chamber placed above the combustion-chamber, in combination with the coal distilling and coking retort extending horizontally through the. combustion-chamber and opening into the generatingchamber, the oil-vaporizing retort located in the fixing-chamber, and having an oil-supply pipe at the top, and the steam and air supply pipes connecting with the generating and the combustion chambers, as described.

5. The closed generator, the communicating combustion-chamber, and the superheating or fixing chamber arranged above the latter, in combination with the coal-retort extending through the combustion-chamber and opening into the generator, means for gradually and continuously supplying the retort with coal, the oil-vaporizing retort arranged in the fixing-chamber, and having an oil-supply pipe, and the connected steam and air supply pipes, for the purpose described. I30

6. The closed generator, the communicating combustion-chamber, and the superheating or ing gas, which consists in raising a body of 80 fixing chamber arranged above the latter, in combination with the coal-retort, provided with feeding mechanism and extending through the combustion-chamber, the oil-vaporizing retort arranged in the fixing-chamber, and having an oil-supply pipe, thestealn-boiler, valved chimney, connecting-flues, and a washer, and the supply-pipes for air and steam connected to the generator and combustion-chamber, for the purpose described.

7 The combination of a generator provided with air and steam pipes, a coking-retort open- I -1ng into and heated by the gases from said generator, air-pump G, air-chamber F, valved pipes F F, a superheater, and a washer, substantially as and for the purpose specified.

8. The combination of a generator provided with air and steam pipes, a coking-retort opening into and heated by the gases from said generator, air-pump G, air-chamber F, valved pipes F F air and steam superheater A, a fixing superheater, and a washer, substantially as and for the purpose specified.

9. The generator A, provided with air and steam super-heating back A, having divisions A and holes A constructed as shown, steampipes O, and air-pipes'F, substantially as and for the purpose specified.

10. The combination of generatorA, superheater B, retort E, plunger R, and hopper Q, substantially as and for the purpose specified.

11. The combination of generator A, superheater B, retort E, plunger R, means to reciprocate said plunger, hopper Q, and means to agitate the carbon in said hopper, substantially as and for the purpose specified.

12. The combination of generatorA, having steam and air pipes, superheater B, vaporizing-retort H, oil-pipe h, and retort E, substantially as and for the purpose specified. v

13. The combination of generator A, having steam and air pipes, superheater B, vaporizing-retort H, oil-pipe h, retort E, and means to feed coal-dust through said retort, substantially as and for the purpose specified.

14. The combination of generatorA, having steam and air pipes, superheater B, vaporizing-retort H, oil-pipe h, retort E, flues I 1 valve I, boiler I, pipe J, washer K, chimney L, and valve L, substantially as and for the JOHN L. STEWART.

\Vitnesses:

R. M. HUNTER, B. S. CHILD, Jr. 

